1. Field of the Invention
The present invention relates to an apparatus for penetrating and for observing penetration of body tissue. More particularly, the present invention relates to a trocar assembly having an endoscope or laparoscope inserted therethrough to provide visual observation during penetration of the peritoneum or other body tissue.
2. Description of the Related Art
Endoscopic surgical procedures, that is, surgical procedures performed through tubular sleeves or cannulas, have been utilized for many years. Initially, endoscopic surgical procedures were primarily diagnostic in nature. More recently as endoscopic technology has advanced, surgeons are performing increasingly complex and innovative endoscopic surgical procedures. In endoscopic procedures, surgery is performed in any hollow viscus of the body through a small incision or through narrow endoscopic tubes (cannulas) inserted through small entrance wounds in the skin. In laparoscopic procedures surgery is performed in the interior of the abdomen.
Laparoscopic procedures generally utilize instrumentation that is internally sealed to inhibit gases from entering or exiting the body through the laparoscopic or endoscopic incision. This is particularly true in surgical procedures in which the surgical region is insufflated. Moreover, laparoscopic and endoscopic procedures often require the surgeon to act on organs, tissues and vessels far removed from the incision, thereby requiring that any instruments to be used in such procedures be of sufficient size and length to permit remote operation. Typically, after the surgical region is insufflated, trocars are used to puncture the body cavity and include a cannula which remains in place for use during endoscopic procedures. Generally, trocars used during such procedures include a stylet having a sharp tip for penetrating the body cavity positioned coaxially within protective tubes to protect a patient or surgeon from inadvertent contact with the tip. An example of a known trocar is described in commonly assigned, U.S. Pat. No. 4,601,710 to Moll. Most currently used trocars rely on protective tubes or relative retraction of the tip to prevent inadvertent contact with tissue.
The present invention provides a trocar assembly for observing the penetration of the peritoneum or other body portions. The trocar assembly of the present invention provides an improved window structure for passing optical images to an imaging system inserted into or formed within the trocar assembly, which provides a clear and bright image of the body tissue being penetrated. The assembly also includes a light pipe for passing illumination light to body tissue. In addition, the present invention provides an improved cutting tip for penetration of body tissue.
The present invention relates to a trocar which includes a cannula assembly, an obturator assembly and an image passing system. The cannula assembly includes a cannula housing and a cannula sleeve extending from said cannula housing. The obturator assembly includes an obturator sleeve having a proximal end, a distal end and a longitudinal bore therebetween which are configured for coaxial alignment with the cannula assembly.
An image passing member is positioned at the distal end of the obturator sleeve and is provided to permit passage of optical images into the longitudinal bore of the sleeve and permit passage of illumination light to body tissue. A tissue penetrating member, such as a blade, is positioned adjacent the distal end of the obturator sleeve and distal to the image passing member and is preferably movable between non-deployed and deployed positions. The tissue penetrating member is configured to facilitate observation of body tissue simultaneous with penetration of body tissue.
In the preferred embodiment, the image passing member is an optical with substantially flat surfaces for receiving optical images. Alternatively, the optical window includes at least one conical surface for receiving the optical images.
Image transferring means, such as an endoscope, is preferably removably positioned within the longitudinal bore of the obturator sleeve and is provided to transmit illumination light through the image passing member to the surgical site and to transmit optical images from the image passing member to a proximal end of the obturator housing for subsequent viewing by the surgeon.
The tissue penetrating blade is operatively associated with an actuating member positioned within the obturator housing. Preferably, the actuating member is configured to move the blade to a deployed position and to automatically move the blade to a non-deployed position after the blade has been deployed.
In the preferred embodiment, the actuating member includes a blade drive member slidably positioned within the obturator housing and operatively connected to the blade, and a trigger member which is pivotally connected to the obturator housing. An automatic release member is operatively associated with the trigger member and the blade drive member so that when the blade is moved to the deployed position, the release member actuates to facilitate movement of the blade to the non-deployed position.